As described in PTL 1, an example of a known touch panel that detects a contact position of a contact operation performed by a user includes a light guide plate that faces a display screen, a light source that emits light toward the light guide plate, and a light-receiving element that faces a side end surface of the light guide plate. The touch panel is an FTIR touch panel that detects a contact position at which a detection target, such as a finger or a pen, comes into contact with the light guide plate by detecting scattered light generated when the detection target comes into contact with light guide plate with the light-receiving element.
PTL 2 to PTL 10 listed below propose FTIR touch panels in which light emitted from a light source is incident on a light guide plate through a prism joined to the light guide plate.